Thomas dowmaist



(No Model.)

T. BOWMAN.

. LOCK.

No. 595.290. Patented Dec. 14,1897.

F' I G I- Unrrrnn STATES PATENT OFFICE.

THOMAS DOXVMAN, OF CHESTER, ILLINOIS.

LOCK.

SPECIFICATION forming part of Letters Patent No. 595,290, dated December14, 1897. Application filed November 23, 1896. Serial No. 613,165. (Nomodel.)

To ctZZ whom it may concern.-

Be it known that LTHoMAs DowMAN, a citizen of the United States,residing at Chester, in the county of Randolph and State of Illinois,have invented certain new and useful Improvements in Door-Locks; and Ido hereby declare the followingto be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

This invention relates to improvements in locks, and has more particularrelation to lock attachments for securing the bolt in its shot position.

The invention consists of certain novel constructions, combinations, andarrangements of parts, all of which will be hereinafter moreparticularly set forth and claimed.

In the accompanying drawings, forming part of this specification, Figure1 represents a side elevation of a door provided with my improvedbolt-lock attachment,the position of the bolt being shown in dottedlines, and the locking-plunger being in its withdrawn position. Fig. 2represents a broken central vertical section through said door on theline of my said improved bolt-locking device, the plunger being in itsoperative position within the bolt. Fig. 3 represents a similar Viewwith the plunger withdrawn into its inoperative position. Fig. 4represents an end elevation of the door with a modified form of myattachment applied thereto, a portion of the same being shown insection; and Fig. 5 represents a similar view to Fig. at of another formof my invention.

Ain the drawings represents the door, B the lock-bolt, and G my improvedbolt-lockin g attachment. Said attachment comprises a casing 0, adaptedto be secured to the inside of a door, and a plunger 0, locking in saidcasing. A coil-spring c surrounds said plunger and bears with one endagainst the lateral pin 0 mounted in said plunger and with its oppositeend against an annular flange 0, formed about the mouth of the aperturethrough the casing C. An operating-handle 0, provided with a circularbifurcated head 0, is pivoted eccentrically about the upper end of saidplunger 0 by means of a pivot-pin 0 A suitable aperture is formedthrough the door to permit the plunger cto reach the bolt B and enter asuitable aperture cut therein to lock it in its shot position.

It will be observed from the foregoing description that when the handle0 is turned in the position shown in Fig. 2 the plunger 0' will bereleased and forced inward to engage the aperture in the bolt B by meansof the coil-spring 0 When said handle c is rotated, the periphery of thecircular portion 0 will engage the flange c and withdraw the plunger cfrom the bolt and hold it in said withdrawn position. It will beobserved that by this means after the bolt B has been once shot and theplunger 0 allowed to project inward, so as to engage the aperturetherein, said bolt cannot be withdrawn or unlocked, either by a key fromwithout or any other means, until the said plunger has first beenwithdrawn. By this peculiar construction the lock is made practicallyburglar-proof, as no instrument from the outside of the door can reachand turn the handle 0 up, so as to withdraw the plunger.

In the modified form of myinvention shown in Fig. 4 the construction issubstantially the same, with the exception that the plunger is providedat its outer end with a head 0, having a semicircular portion 0 Asemicircular projection o is formed on the outer end of the casing, sothat when said head 0 is pulled out and rotated the projection 0 willoccupy a position above the projection o and thus prevent the plungerfrom entering it again until the head c is again rotated to bring thesaid projections into the same horizontal plane. In all other respectsthis modified construction of my invention is substantially the same asthat hereinbefore described.

My said improved lock-fastener may be applied to ordinary locks now inuse, in which the bolt is provided with a recess or slot capable ofreceiving the plunger 0.

In the construction shown in Fig. 5 the outer end of the casing isprovided with two grooves f f, arranged upon diametrically oppositesides and adapted to receive the ends of a T-handled plunger f. WVhenthis plunger is withdrawn and turned, the arms at the end of the samelie against the outer end of the casing at right angles to the groovesff.

mally force the plunger forward to engage a suitable aperture formed inthe bolt, an operating-lever mounted on the protruding end of theplunger and adapted to engage the casing to Withdraw said bolt againstthe tension of the spring, substantially as described.

2. In a lock-fastenin g device, the combination with a suitableattaching-casing, of a plunger mounted in the same and adapted toproject through the door into a suitable aperture formed in the bolt, aspring connecting said plunger and casing for normally projecting theformer into the aperture of the bolt, and a handle having a circularenlargement and eccentrically pivoted upon the outer end of said plungerso'that its periphery engages the outer end of the casing and Withdrawsthe plunger therefrom against the tension of the spring, substantiallyas described.

'3. In a lock-fastening device, the combination with a suitable casing,of a plunger mounted therein and adapted to project through the doorinto a suitable aperture formed 1n the bolt, a coil-spring surroundingsaid plunger and forcing the same normally inward, and anoperating-handle having a circular enlargement and eccentrically pivotedupon the outer end of said plunger so that its periphery engages theouter end of the casing to Withdraw the plunger therefrom against thetension of the spring, substantially as described.

4. In a lock-fastening device, the combina- I tion With a suitableattaching-casing, of a spring-pressed plunger mounted in the same andadapted to project through the door into a suitable aperture formed inthe lockingbolt, and an operating-handle having a circular bifurcatedhead that is eccentrically pivoted upon the outer end of said plungerrodso that the respective peripheries of said bifurcated portion engage theouter end of the casing upon each side of the plunger-rod to Withdrawthe latter from the casing against the tension of its spring,substantially as described.

In testimony whereof I have signed this specification in the presence oftwo subscribing Witnesses.

THOMAS DOWVMAN.

Witnesses:

J. M. TINDALL, LoUIsE DOWMAN.

